Andesitic eruption is more fluid and mobile than basaltic eruptions.

Choose the correct statements?

a) Only 1

b) Only 2

c) Both 1 and 2

d) None of the above.

Q13. Which of the following term regarding intrusive volcanic landforms are correctly matched?

1. Sill- lava solidifies almost perpendicular to the ground.

2. Phacolith-found at the base of syncline of top of anticline.

3. Laccoliths-when lava settles in a saucer shape while moving on a horizontal weak plane.

Choose the incorrect statements?

a) Only 1

b) Only 2

c) Both 1 and 3

d) All are correct.

Q14. Match the following:

List A List B

Calderas Depression by explosive volcanoes

Deccan traps Lava solidified perpendicularly

Dykes Cooling in the crust

Plutonic rocks Flood basalt provinces

Choose the correct answer:

A B C D

a) 1 2 3 4

b) 1 4 2 3

c) 3 4 2 1

d) 2 4 1 3

Q15. Which of the following is not the reason to induce as earthquake?

a) Re-emergence of old fractures in the craton.

b) Small plates frequent interaction in Mediterranean Sea region.

c) Human induced deep sea mining and nuclear testing.

d) All the above can be probable reason to induce quakes.

Q16. Consider the following statements regarding the types of earthquakes:

Tectonic earthquakes are generated due to sliding of rocks along the fault line.

Collapse earthquakes occur due to chemical or nuclear device explosion.

Choose the correct answer:

a) Only 1

b) Only 2

c) Both 1 and 2

d) None of the above

Q17. Which of the following statements regarding measurement of earthquakes are correct?

a) The point directly above the focus on the surface is called the epicenter. It the first point to obverse the waves.

b) The richer scale relates to the energy released during quake.

c) The intensity scale relates to the amount of damage caused.

d) All statements are true.

Q 18.Which of the following statement regarding the Pacific Ring of Fire are correct?

a) The Ring of Fire is a direct result of plate tectonics that is the movement and collisions of lithospheric plates.

b) It is the most seismically active region of the world as about 90% of the world’s earthquakes occur along the Ring of Fire.

c) The active seismic region of the Indian Himalayas also considered as part of pacific ring of fire.

d) Both (a) and (b)

Q19. Consider the following statements regarding the geological phenomenon tsunami?

Tsunami waves have longer wave lengths and hence difficult to discover from off shore.

Tsunami waves are majorly generated due to earthquakes on oceanic crust.

Choose the correct answer:

a) Only 1

b) Only 2

c) Both 1 and 2

d) None of the above

Q20. Match the following famous places with type of volcanism:

List A List B

Cinder cone Mt.Fiji

Composite cone Mt. Paricutin

Hot spot volcanism Mt. Etna

Mediterranean volcanism Reunion island

Choose the correct answer:

A B C D

a) 1 2 3 4

b) 2 1 4 3

c) 3 4 2 1

d) 2 4 1 3

Answers

1.C

Explanation:

Latitude of a place is measured as the angular distance of the place from the equator. All latitudes also called as parallels are concentric circles.

Equator is the largest latitude of earth dividing the earth in two equal halves. Longitude of a place is measured as the angular distance of the place from the prime meridian .Longitudes also known as meridians play a significant role in measuring the time zone of an area. 0 degree longitude is Greenwich in UK and 180 degree is the International Date Line.

2. D

Explanation:

Daytime saving has nothing to do with increase working hours. The working hours remain the same but the shift becomes one hour ahead.

Daylight saving time (DST) or summer time is the practice of advancing clocks during summer months by one hour so that evening daylight lasts an hour longer i.e fully utilizing the surplus sunlight in summers while compensating the short day length in winters. Typically, regions with summer time adjust clocks forward one hour close to the start of spring and adjust them backward in the autumn to standard time. People use the terms “spring forward” and “fall back” when referring to this.

3. D

Explanation:

The number of time zones a country practices mostly depends on the size of the country .For example, it’s impossible for a country as huge as Russia with the area of 17.1 million km⊃2; to process on only one time zone –this might create a problem of day-night difference within the same country .So Russia has 11 time zones and USA has 6 time zones. However there are certain exceptions like china which works on only one time zone despite its size. Indian Standard Time is calculated on the basis of 82.58° E longitude and its uniform all around the country.

4.D

Explanation:

The International Date Line is an imaginary line of longitude on the Earth’s surface located at about 180 degrees east (or west) of the Greenwich Meridian and marks the divide where the date changes by one day. It makes some deviations from the 180-degree meridian to avoid dividing countries in two, especially in the Polynesia region.

The time difference between either sides of the International Date Line is not always exactly 24 hours because of local time zone variations.

If you travel around the world, changing standard time by one hour each time you enter a new time zone, then a complete circuit would mean that you adjusted your clock or watch time by 24 hours. This would lead to a difference of one day between the date on your clock and the real calendar date. To avoid this, countries are on either side of the International Date Line which runs down the middle of the Pacific Ocean. If you cross the date line moving east, you subtract a day, whereas if you are moving west you add a day.

5.B

Explanations

The earth’s revolution in the inclined position in the elliptical orbit leads to variation in the length of day and nights all over the globe.

As the earth axis makes an angle of 66 1/2 degrees with the plane of elliptic, during the month of June when it is summer over the northern hemisphere, the sun rays directly fall on the tropic of cancer. So this leads to longer days and shorter nights in the northern hemisphere area leading to increase in the day light as well. Length of day and night does vary according to the season and latitudinal position. At the equator the day and night are mostly of same lengths all round the year.

6. A

Explanation:

As we know Earth rotates 360 ° in 24 hours,

Per hour earth will cover (360/24 ) 15°degrees.

Therefore,15 degree= 1 hour and

1 degree = 4 minutes

Now according to the given problem, we know while moving east from Greenwich the time increases.

So difference between GMT and IST (82.5 degree)= 82.5-0 is 82.5 degrees

And 1 degree =1/15 hours

So 82.5 degree= 1/15 X 82.5=5.5

That is 5 and a half hour ahead

So, 5:30 P.M

7. C

Explanation:

Latitude of a place is measured as the angular distance of the place from the equator. All latitudes also called as parallels are concentric circles. So,

Equator is the largest latitude of earth. The equator is the only line of latitude which is also a great circle — that is, one whose plane passes through the center of the globe. The plane of Earth’s equator when projected outwards to the celestial sphere defines the celestial equator.

Sites near the Equator, such as the Guiana Space Centre in Kourou, French Guiana, are good locations for spaceports as they have a faster rotational speed than other latitudes; the added velocity reduces the fuel needed to launch spacecraft. Because the Earth spins to the east, spacecraft must also launch to the east (or to the southeast or northeast) to take advantage of this Earth-boost of speed.

8. C

Explanation:

The Tropic of Cancer position is not fixed, but varies in a complicated manner over time. It drifts south almost half an arc second of latitude per year .North of the tropic are the subtropics and the North Temperate Zone.

The equivalent line of latitude south of the Equator is called the Tropic of Capricorn, and the region between the two, centered on the Equator, is the tropics. Starting at the Prime Meridian and heading eastward, the Tropic of Cancer passes through 16 countries: Algeria, Myanmar, Bahamas, Saudi Arabia, Niger, China, India, Bangladesh, Libya, Taiwan, Mauritania, United Arab Emirates, Egypt, Mexico, Oman, and Mali

9. B

Explanation:

Chaibagaan Time was a daylight schedule introduced by the British tea planters more than 150 years ago which was one hour ahead of IST.

This was done to improve productivity by optimizing the usage of daytime. Since Independence, Assam has been following IST for the past 66 years.

Recently, the administration of the Indian state of Assam now wants to change it’s time zone back to Chaibagaan time to conserve energy and improve productivity. Indian government didn’t accept to such a proposal.

10. A

Explanation:

The International Date Line is an imaginary line of longitude on the Earth’s surface which marks the divide where the date changes by one day. It makes some deviations from the 180-degree meridian to avoid dividing countries in two zones. If you cross the date line moving east, you subtract a day, whereas if you are moving west you add a day.

So, statement 1 and 2 are correct.

As we know Earth rotates 360 ° in 24 hours,

Per hour earth will cover (360/24) 15°degrees.

Therefore,15 degree= 1 hour and

1 degree = 4 minutes

Now according to the given problem, we know while moving east from Greenwich the time increases.

So difference between GMT and IST (82.5 degree)= 82.5-0 is 82.5 degrees

And 1 degree =1/15 hours

So 82.5 degree= 1/15 X 82.5=5.5

That is 5 and a half hour ahead

So, 5:30 P.M

11.B

Explanation:

Flood Basalt volcanoes contains highly fluid lava that flows for long distances.. There can be a series of flows with some flows attaining thickness of more than 50 m. Some parts of the world are covered by thousands of sq. km of thick basalt lava flows Individual flows may extend for hundreds of km.

The Deccan Traps from India, presently covering most of the Maharashtra plateau, are a much larger flood basalt province. It is believed that initially the trap formations covered a much larger area than the present.

12.A

Explanation:

Basaltic eruptions are characterized by low gas content and low viscosity magmas. If the viscosity is low, non-explosive eruptions usually begin with fire fountains due to release of dissolved gases. They occur at mid-oceanic ridge and hot spot volcanism. Basalt is highly fluid –mobile and spread across quietly.

When magma reaches the surface of the earth, it is called lava and it flows downhill in response to gravity as it’s in liquid state. Different magma types behave differently as lava flows, depending on their temperature, viscosity, and gas content.

Explosive or andesitic eruptions are favored by high gas content and high. Explosive bursting of bubbles will fragment the magma into clots of liquid that will cool as they fall through the air. These solid particles become pyroclasts (meaning – hot fragments) and tephra or volcanic ash, which refer to sand- sized or smaller fragments.

They occur at volcanic arcs and volcanic mountains. Andesitic is less fluid mobile and solidifies at short distance due to intense pressure developed inside.

13.C

Explanation:

Laccoliths are large dome-shaped intrusive bodies with a level base and connected by a pipe-like conduit from below.

Lopoliths are formed when the lava moves upwards, a portion of the may tend to move in a horizontal direction wherever it finds a weak plane and develops into a saucer shape concave to the sky body.

Phocoliths are wavy mass of intrusive rocks found at the base of synclines or at the top of anticline in folded igneous country.

The near horizontal bodies of the intrusive igneous rocks are called sill or sheet, depending on the thickness of the material.

Dykes are formed when the lava makes its way through cracks and solidifies almost perpendicular to the ground.

14.B

Explanation:

Calderas are the most explosive volcanoes. They are usually so explosive that when they erupt they tend to collapse on themselves rather than building any tall structure. The collapsed depressions are called calderas.

Flood Basalt Provinces are volcanoes outpour highly fluid lava that flows for long distances. There can be a series of flows with some flows attaining thickness of more than 50 m. The Deccan Traps from India, presently covering most of the Maharashtra plateau, is a much larger flood basalt province.

Dykes are formed when the lava makes its way through cracks and solidifies almost perpendicular to the ground. It gets cooled in the same position to develop a wall-like structure.

The lava that is released during volcanic eruptions on cooling develops into igneous rocks. Depending on the location of the cooling of the lava, igneous rocks are classified as volcanic rocks (cooling at the surface) and plutonic rocks (cooling in the crust).

15.D

Explanation:

Mostly earthquakes are caused due to plate boundary interactions like compressive, divergent and transverse boundary.

The release of energy occurs along a fault. A fault is a sharp break in the crustal rocks. Rocks along a fault tend to move in opposite directions. As a result, the blocks get deformed and eventually, they slide past one another abruptly. This causes a release of energy, and the energy wave travel in all directions.

Earthquake-like seismic waves can also be caused by explosions underground. These explosions may be set off to break rock while making tunnels for roads, railroads, subways, or mines. The largest underground explosions, from tests of nuclear warheads (bombs), can create seismic waves very much like large earthquakes.

16.A

Explanation:

Among different types of earthquakes, the most common ones are the tectonic earthquakes. These are generated due to sliding of rocks along a fault plane. A special class of tectonic earthquake is sometimes recognized as volcanic earthquake. However, these are confined to areas of active volcanoes.

In the areas of intense mining activity, sometimes the roofs of underground mines collapse causing minor tremors. These are called collapse earthquakes. Ground shaking may also occur due to the explosion of chemical or nuclear devices. Such tremors are called explosion earthquakes.

The earthquakes that occur in the areas of large reservoirs are referred to as reservoir induced earthquakes.

17.D

Explanation:

The release of energy occurs along a fault. Rocks along a fault tend to move in opposite directions. As a result, the blocks get deformed and eventually, they slide past one another abruptly. This causes a release of energy, and the point where the energy is released is called the focus of an earthquake, alternatively, it is called the hypocentre. The point on the surface, nearest to the focus, is called epicentre. It is the first one to experience the waves. It is a point directly above the focus.

The earthquake events are scaled either according to the magnitude or intensity of the shock. The magnitude scale is known as the Richter scale. The magnitude relates to the energy released during the quake. The magnitude is expressed in absolute numbers, 0-10. The intensity scale is named after Mercalli, an Italian seismologist. The intensity scale takes into account the visible damage caused by the event. The range of intensity scale is from 1-12.

18.D

Explanation:

The Ring of Fire is a direct result of plate tectonics: the movement and collisions of lithospheric plates. The Ring of Fire is a major area in the basin of the Pacific Ocean where a large number of earthquakes and volcanic eruptions occur.

In the horseshoe shape, it is associated with a nearly continuous series of oceanic trenches, volcanic arcs, and volcanic belts and plate movements. It has more than 75% of the world’s active and dormant volcanoes and about 90% of the world’s earthquakes occur along the Ring of Fire.

The Ring of Fire is sometimes called the circum-Pacific belt. The next most seismically active region (5–6% of earthquakes and 17% of the world’s largest earthquakes) is the Alpide belt, which extends from Java to the northern Atlantic Ocean via the Himalayas and southern Europe.

19.C

Explanation:

The most relevant reason/ cause of tsunamis are large earthquakes at the seafloor, when large slabs of rock are forced to move past each other suddenly causing the overlying water to move. The resulting wave moves outwards and away from this event. Underwater landslides can cause tsunami, and so can land which slumps into the ocean.

20.B

Explanation:

The oceanic and continental plate collision results violent andesitic volcanic mountains containing cinder cone where viscous lava solidifies at vicinity for example Mt. Paricutin, Mexico.Volcanic Mountains in which each new eruption bring in new layers of ash or lava results in composite cones like Mt. Stromboli, Mt. Vesuvius and Mt. Fuji.

The basaltic highly mobile magma from deep interior is erupted on a fixed hot spot as plate move forming the Island arc in the direction of plate movement. Examples of these island arcs are Hawaii, Reunion, Kurile, Aleutian etc

The Breaking up of Mediterranean plates into multiple blocks causes frequent interactions and andesitic eruption for examples Mt. Etna and Mt. Vesuvius.